Control valve



Patented .July 11,1933

UNIT-ED stares JULIUS name, or nas'rou, ranusnvama, assrenon fro INeEnsoLL-am comm,

0F JERSEY CITY, NEW JERSEY, A CORPORATION OF JERSEY common VALVE Application filed April 11,

vention and showing it applied to a compressor illustrated in sectional plan view.

Referring more particularly to the drawing, the'control valve which is designated in general by A is shown applied to a compressor B comprising a cylinder 0 and end heads D and E.

The compressor B may as shown he of the double acting type wherein the working substance is compressed in the opposite ends of the cylinder by a'piston F reclp'rocable therepressed fluid flows into a conduit mined value.

in. Each end of the cylinder C is provided with inlet and discharge valves G and H res ectively for controlling the admission of uid intothe cylinder andthe discharge of the compressed fluid from the cylinder.

The medium intended to be compressed may be conveyed to the'inlet valves G by an inlet passage J in the cylinder G. Upon being compressed in the cylinder the pressure fiui passes through the dischar e valves H into a discharge chamber K, also m'the cylinder C. The discharge chamber K is provided with an outlet opening L through which the com- 7 0 leading to a store e receiver P.

Usua y compressors of the type illustrated are provided w1th regulating means for maintaining the receiver presn're' at a predeter 4 Such means may be associated with the inlet or discharge valves ofthe compressor or may consist,-as shown, of clearance control valves Q adapted to control communication between the inder C and clearance (pockets. R in or adjacent .the c linder The I clearance pockets for eac end of the cylinder may and forming a part thereof is a longituends of the cyl-" 1932. mm No. 604,496.

consist of any desired number, depending upon the steps of unloading which it may be desired to obtain, and may be suitably proportioned to effect either partial orcomplete unloading of the cylinder ends.

The form of clearance valve Q, selected for. illustrative purposes, comprises a casin S threaded into the wall of the cylinder and extending into the clearance pocket wherewith itis associated: Within the-casa valve V adapted-to control a port W which affords communication between the clearance pocket R and the end of the cylinder C. Within the chamber T is aspring X to normally maintain the valve V in the closed p0 PATENT orFrcE .mg S is'aschamber T to receive a head U of sition, and in the casing S is a pa ssage .Y through which pressure fluid flowsinto the inner. end of the chamber T to act against an actuating surface Z atl thejuncture of the head U and the valve p v The control valve A, constructed in'acoordance with the practice of the invention, comprises a casing 12 having a valve chamber a which extends longitudinally therethrongh.

A closure is provided for one end of the valve chamber 0 by a head (1, and'in the op osite end of the valve chamber 0 is a threade portion e to accommodate a threaded plug 7 having a lock nut g thereon which may seat against the end of the casing b to retain the P 8 he end f a spring h disposed in the chamber 0 to act against a valve 7' for normally maintaining the valve 7' seated against the head (Z. which is of the reciprocatory The valve 7',

type comprises an intermediate flange k and end heads 0 and 12 connected to the flange k 'by' reduced stems. qand r. V The spring]; acts on the head? .er end of the valve constitutes an actuatingsurface '8 which is constantly exposed to pressure fluid. The ressur'e fluid thus acting against the actuating surface s is introduced into the end of the chamberc through a port 25 f securely in any position in which it ma be placed."

plug 7 serves in pa'rtas a seat for an in the head (i and a pipe a leading from the storage receiver P.

The pipe M has an extension '0 which is connected to an intermediate portion of the casing 12 and opens into a supply passage w in the wall of the casing b. The supply passage w extends longitudinally of the'casmg b and has a pair of ports a and y WhlCh, when the valve 7' is seated against the hand d, are closed by the flange k and the head p, respectively, of the valve. v

In the casing b and at a point intermediate the outlet openings m and y is an outlet port 2 into which is threaded an end ofa pipe 2 connected to a clearance valve mechanism Q for introducing pressure fluid into its passage Y. Similarly, at a point between the outlet port a and the head at is a second outlet port 3 to which is connected a ipe 4 leading to the pamage Y of a second valve mechanism Q. The ports a and 3 are so located that they will at all times lie between adjacent enlarged portions of the valve j, such as the heads 0 and p, and the flange k.

In order to communicate theoutlet ports a and 3 with the atmosphere the-casing b is provided with vents or exhaust ports 5 and 6 located between their associated outlet ports and the head d. Preferably the ports 6 is located closely adjacent the head 0- of the valve so that upon movement of the valve j under the influence of pressure fluid acting against the actuating surface s the port 6 will im mediately be closed by the head 0, and the exhaust port 5 is so located that it will be closed by the flange 72, whereby it is controlled, prior to the uncovering of the outlet port 3 by the head p.

On the end of the casing 21 adjacent the threaded portion 6 is an arm 7 to which is secured, as by means of a screw 8, a flange 9 that lies acrossthe end of the casing 12. The flange 9 carries a cylindrical extension 10 which extends through a bore 11 in the plug 7 and the free end 12 of the extension lies in the path of the valve 3} to act as a fixed stop for said valve. Within the extension 10 is a bore 13 for the accommodation of a spring 14 which seats with one end against a screw tension 10 to 15 threaded into the extension 10. The opposite end of the sprin 14 bears against a plunger 16 slidable in t e-end 12 of the exserve as a yieldable stop for the valve j.

The operation 'ofthe device is as follows:

I With the plug 7 and the screw 15 adj ustedto tension the springs in and 14 to'pressures corresponding to redetermined receiver pres-. sures at which it is intended to effect partial or full unloading, of the compressor, pressure fluid will flow from the storage receiver P through the pipe to into the end of the valve chamber 0 and into the supply passage '20.

When' the pressure of the fluid acting against the actuating surfaces reaches that value for which the spring h is adjusted to yield, the valve j will be actuated in the direction of thestop members 12 and 16. Immediately upon starting of the valve in this direction the head 0 will cover the exhaust port 6. Upon further movement of the valve in the same direction the port 02 will be uncovered by the flange k and, pressure fluid then flows through the valve chamber,fthe port 3, the pipe 4 and the passage Y into the inner end of the chamber T and will act against the actuating surface Z to open the valve V. In this way the one .end of the cylinder C will be placed in communication with the clearance pocket R associated there- 1 combined pressures exerted by the springs h f and 14.

When this further predetermined higher pressure is attained in the-receiver P the valve 3' will be further actuated in. the directionof the stop members. During this movement of the valve, the flange k covers the exhaust port 5 and upon further slight movement of the valve in the same direction the head 0 uncovers the port 3/, thus admitting pressure fluid through the associated passages into a second clearance valve mechanism Q for effecting additional unloading of the compressor.

About the time the valve 9' uncovers the port y'it will seat against the fixed stop 12 which is so located that, in this position of the valve 9', the port as will be in full communication with the outlet port 3 and the.

Both ends port 3 with the outlet port a. of the. compressor cylinder C-may then be unloaded in accordance with the, capacities of the clearance pockets R associated there- .with.

If, during further operation-of the compressor and due to the consumption of pressure fluid thereceiver pressure drops below that exerted by the springs h and 14 the said springs will actuate the valve 7' in the direction of its initial position. During the movement of the valve in this direction the port y will first be closed. Thereafter the port 5 will be uncovered by the flange It so that the pressure fluid in the clearance valve mechanism'Q, associated with that portion ofthe valve chamber 0 will be exhausted to the atmosphere, thus again loading that end of the cylinder 0. 1

Upon a further reduction of the value of the pressure fluid in the receiver P the spring It will actuate the valve against the head d actuate the valve for establishing communicaports, a

thus cutting of the port wand communicating the port 3 with the'exhaust port 6. In this way the pressure fluid in' the second clearance valve mechanism- Q be exhausted to the atmosphere, therebyallowing its spring X to close the valve V and gam load that end of the compressor cilin er 0.

As will be readily understood, w enever it may be desired to have thevalve 7' act for loading or unloading the several ends of the cylinder 0 at various predetermined pressures in the storage receiver the springs h and 14 may be tensionedaccording y byadjusting the plug 7 and the screw 15 or, should it be desired to simul ing of both ends of the cylinder, the plu and the screw 15 may be adjusted-to ena lo the valve 7' to move uninterruptedly against the stop member 12.

I claim: 7 y

1. A control valve comprising a casing having a chamber and inlet and outlet ports for the chamber, a valve in the valve chamber, an actuating surface on the valve constantl exposed to pressure fluid, a spring seat on the valve exposed to atmospheric pressure, a spring ing a apted to yield to a predetermined pressure acting against the actuating surface for establis 'ng communication between an inand an outlet'p'ort, spring seat and to yield upon crease in the (value of the fpressure fluid actin against the actuating sur ace to establish communication between a second inlet port and a second outlet port. I

2. A control valve comprising a casing having'a chamber and-inlet and outlet ports for the chamber, a chamber havingv an actuatin surface conuid tending to tion between. the inlet and outlet pring seat on the valve exposedto atmospher- 1c pressure, and a plurality of yieldable "stop means acting successively against the s taneously efi'ect unloadadapted to engage th I the chamber, acting against the spring seat and beto hold the chamber and: being adapted'to yield to a predetermined pressure a g surface for communicating one inlet reciprocable valve in 'the'valve v seat to hold the valve in different positions along the length of the chamber and being adapted to yield to predetermined pressures m c against the actuating surface for communicating the inlet ports with the outlet ports.

3. A control valve comprising a casing having a chamberand inlet a (1 outlet ports for the chamber, a reciprocab e valve in the chamber havingan actuatin surface constantly exposed to pressure uid, a s rin'g seat on the valve exposed to atmosp eric pressure, a spring acting against the spring ed to yieldto a predetermined pressure f against the actuating surface to establish communication between an inlet port and an out- I let port, and a spring-pressed stop member e spring seat and bein adapted to y eld to a higher predetermin pressure against the actuating surface to comseat to hold the valve closed and being adaptmunlcate a second inlet port with a second outlet port.

y 4. A control valve comprising a casing having achamber and inlet and outlet orts for a reciprocable valve in t e chamher and havin an actuatin stantly exposefto pressure finid, a spring seat on the valve exposed to atmospheric pressureQa spring acting against the spring seat the valve in one limiting position in gainst the actuati portv with. an outlet port, a spring-pressed stop member positioned to engage the spring seat. and being adapted to yield termined pressure against the actuating surfaceto enable the valv to'communicate a pressed member."

surface conto a higher prede- In testimony whereof I have signed this n specification. ,v v

r NAAB. 

